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Thursday, 19 May 2022

Ancient computers

Ancient computers

It was 1984, and I was establishing myself as some sort of PC guru. I was writing for most of the PC magazines, and for the IBM PC User Group newsletter, and for the stockbroker that was my day job (my best article was "The bus has no driver", which countered the idea that economies are run by some elite person or group; in this case, the Saudi oil minister).

I realised that I was spending an hour commuting, each way, and those hours weren't productive. So when I saw the NEC PC-8201a, I thought, I can use this on the train.

It's small, A4 sized, and fitted nicely in my briefcase. It ran off four AA batteries (and I kept a spare set handy, It had 28kb of usable memory, which was enough for two articles.

It cost me £137, because I got it as a dealer from Pete and Pam (later P&P Distribution) and it was a fantastic bargain. The keyboard is a good, full-travel keyboard, the cursor control are the most logical I've ever seen. The only drawback was the screen, which was 40 columns wide and 8 deep, but I could live with that.

I'd spend the commute writing an article using the TEXT editor, download it to a PC using the TELCOM program. On the PC, I would spell-check it, reformat it to 78 columns, and print it out. Yes, in that days, even PC magazines didn't have computers, and needed printed text.

I still have that PC8201a. I got it out recently, and it didn't work. I opened up the battery case, and one of the traces was badly corroded, so I bypassed it with a bit of wire, and that made the battery case work. Then I struggled to get the NEC working, because I'd forgotten that there's an on/off switch on the side.

Now it works perfectly.

Bill Gates told me that the Basic for that computer was the last Basic that he wrote himself.

The next computer was the Sinclair Z88, which also ran off AA batteries, and had an 80 column screen. But that screen was hard to read, the keyboard was terrible, and I hardly used it. It didn't work when I tried it recently.

Then Amstrad brought out the PC100, another nice A4-sized computer using AA batteries. I got one for each of my daughters, but I don't think they ever used them. Now when I tested them, one worked perfectly, the other didn't.

Another nice buy was the Psion series 3a. This was a pocket sized computer that ran Dos. The other good thing about it is that it had a built-in database, and you could put your contact details into it, including phone number. Then you could phone the contact, and the Psion would emit the touch-tone signals to your phone, and you didn't need to dial. OK, not as slick as today's smartphones, but this was 35 years ago, and portable phones barely existed.

Another pocket size computer was the Toshiba Libretta. That came with Windows 95. I got it because I thought I'd use it for powerpoint presentations. In practice, it really wasn't very useful.

I also had another battery powered computer, but I don't remember the name, it wasn't useful at all, and it's probably buried somewhere ni a cardboard box. Its distinguishing feature was that it use 1 1.2 inch floppy disks.

If someone asked me to recommend a portable, battery-powered computer to be used as a writing system, I would definitely go for the NEC. They are still available on eBay, but at twice the price I paid.  runner up would be the Tandy 100, or TRS-80 100. Same machine, but an inferior keyboard layout.  The Olivetti M10 is the same. But they aren't commonly available.

Second would be the Amstrad, which you can get on eBay for £60 or so.



Sunday, 10 April 2022

Facebook hello

Facebook hello

For no apparent reason, Facebook has restored my account




Tuesday, 5 April 2022

Disk failure

Disk failure

I got my first warning, when part of an important file, that was text-only, became corrupt and had binary stuff in it. I was able to replace the binary from a backup.

Then it happened again. And again. I'm so glad that I use a flat-file text-only database.

This is an important computer, it's the one I do billings from, and is therefore inside the innermost bastion of my firewall. That turned out to be a big problem later.

I used the SMART system, which tells me how many bad sectors there are on the drive, and it was large - and growing fast. This disk was on the verge of failing.

So, first I built a replacement computer. I used an Intel motherboard (I bought a job lot of these a few years ago, and they're great) with the CPU an E7500 dual processor running at 2.93 GHz. I put in 8gb of memory, and an 80gb 2.5 inch drive.

Next, to configure it, I used a 192.168.2.2 ip address, because that's in the range I use for "inside", the innermost bastion. That meant that I couldn't connect it to the usual 10.x.x.x range, it had to connect to the "inside". But the switch that is fed by the "inside" is way across the room, so I cleverly put a switch between the firewall "inside" and the switch across the room. Everything still worked. So I took a feed from the new switch.

That should work, right?

But it didn't. And I still don't know why.

I tried lots of things, such as replacing the new switch, and many others that didn't work.

Eventually, I did a "hail Mary" (an American football term for a desperation move) and slung a 10m cable from the old switch right across the room to the new server, and to my utter astonishment, it worked!

So I loaded up the new server, partly from the failing old one and partly from the backup, installed apache (latest version, and configuring that led to much grief).

Eventually, I got everything working, put the new server in the place where the failing server was, and everything is OK now.





Monday, 4 April 2022

Fetchmail follies


Fetchmail follies

First, I'll explain my email system. It's complicated.

To tell other computers where to send email for me, we use the DNS (Domain Name Service) system. In that, an MX (Mail eXchange) record tells other computers where to send my email. There are two main servers, mail2 and mail1. The MX record tell the priority. So, mail is sent to mail2, unless mail2 isn't working, in which case it goes to mail1. Both are Raspberry Pis, version 1, vintage 2012. I also retreive email from several AOL and Gmail accounts.

Mail1 gets spam, nearly everything. Because it shouldn't be used unless mail2 isn't working. I take advantage of this by setting up a bunch of MX records with even lower priority as spam traps.

But I don't want to visit both computers, so I set up fetchmail, to visit each in turn and use the IMAP protocol to collect unread mail and put it on my email reading computer., xantl. To read mail I use pine or alpine, a text-only reader. That means that I don't have to worry about unpleasant surprises that you can get in web-based readers.

When it gets to xantl, it passes through my mail spam filter,sorting the mail.

So what went wrong? Suddenly, fetchmail stopped fetching mail from mail2 and mail1. I hadn't made any recent changes. This happened a few weeks ago.

So I tried fetchmail -vvv (verbose) but that told me nothing useful.

I tried reinstalling fetchmail. i tried installing fetchmail on another computer. I tried reinstalling dovecot (the IMAP server) on the pis. nothing worked. I tried updating OpenSSL - no joy.

I tried using .forward on mail1, but that didn't help. and all this while, I was reading an dealing with emal on mail2 and mail1.

I tried changing the MX records to a different computer. No use.

Then I did what I should have done in the first place. Google is a great resource, but I also have a file where I keep a record of past problems and thier solitions, and I found this gem.

 To see what fetchmail is doing:
fetchmail -Nvvvd0 --nosyslog

So I did that, and it told that the problem was that fetchmail couldn't negotiate a secure channel with mail1. But I don't need a secure channel because the whole network is secured.


So I added 

 sslproto '' 

to the .fetchmailrc, telling fetchmail not to use secure sockets.

And everything worked!

I think this happened because fetchmail updated itself without telling me. The fact that a couple of weeks of Googling turned up nothing, makes me think that I'm the only person who has ever had this problem. There can't be many people using fetchmail release 6.4.23 to retreive mail from 10 year old Raspberry Pis.



Monday, 7 March 2022

Facebook farewell

Facebook farewell

 I logged in to Facebook, the first time for ages, and I got this:

 

xxxx, Login approval needed
We've noticed a login from a browser, device or location you don't usually use. We need to confirm that it was you before you can get back on Facebook. Learn more

xxxx xxxxxxx Facebook
 
Choose how to confirm that this is your account
 
Complete a few steps to confirm that this is your account
 
 
 
 
So I clicked on continue. After several seconds I got:


 
 
 
Choose an option
How do you want to confirm that this account is yours? You can try any of these options more than once. Learn more
 

Thursday, 3 March 2022

Victory!

 Victory!




In July, I came up with the idea of using a more modern anticoagulant than
Warfarin, which I've been on for 25 years. Warfarin works, but I have to go to
the clinic every few weeks to get tested.

So they said yes, but we need to look at your blood. I gave a sample, And
nothing happened for a couple of months, but then I was contacted And was told
that I have markers. Meaning, a problem.

Part one

So I went to Wycombe hospital, and they gave me a thorough going over. I have
a minor blockage in one of my heart valves, but nothing to worry about. I have
diabetes; blood sugar normal range is 4-7, and mine comes in a 7-9, so only
slight.

And they did a CAT scan, and found a lump, in the duct between my liver and
gall bladder.

After that, everything happened very fast. I had an MRI scan, which confirmed
the lump, and I was told it's 95% likely to be cancer.

50 years ago none of this would have been possible; I had no symptoms, and
felt perfectly healthy. Then they did a PET scan; they put something slightly
radioactive into me, and scanned. A PET scan is a generic cancer detector. I
had to wait weeks for the result, but it came back clean, apart from the known
lump. I had to confess, I cried with joy when they told me this.

So I had a consultation with an oncology expert at Oxford Churchill hospital,
and he explained the options. But there was only one real option.

The liver is the only organ that can regenerate itself. And it comes in two
parts, a small part and a large part - the lump was near the large part. The
plan was to cut off that large part, and then the small part would grow.

But first, I needed three procedures; a procedure is a minor operation. The
first was to put a stent next to the lump, so that bile could flow freely to
the gall bladder. That happened in Oxford Radcliffe.

But it didn't work. They sedated me (meaning, I was asleep). I held a plastic
mouthpiece between my teeth, and they put a tube down my throat and navigated
it with xray assistance down to where it needed to be but they couldn't get it
in place. Worse - one of the risks of this prodecure is peritonitis, and I got
that. I vomited up the contents of my stomach, I had a terrible pain there,
and they shipped me back to Oxford Churchill.

Over the next several days, even the thought of food made me nauseous, and I
was in a lot of pain. They put me on Paracetamol, and a saline drip to keep me
hydrated, and the morphine, which was another drip that I pressed a button
when I needed more - which was often.

After several days, I was feeling a bit better, so they scheduled me for a
repeat of the procedure, except this time they went in through my side. That
worked, and now the bile drained through a tube, into a bag.

So, again some days to recover, and then we faced the next procedure. the idea
was to block the blood supply to the bad part of my liver, so it would start
to shrink, and the good part start to grow.

I was slightly sedated, and lay flat on my back for two hours, and my back
really doesn't like that. then I had to stay in that position for another two
hours, until eventually I could move and relieve the pain. That was 100%
successful. A few days later, they did the second part of that, which
consisted of blocking the outflow.

All this was to get me ready for the main event.

I got out of hospital 17 days after I went in. I still had the drain, but it
didn't drain externally.

While I was in hospital, I lost 18 pounds, mostly because of the peritonitis.
But I felt OK when I left, although with very little appetite.

That was November 22. I was told to get as fit as possible for the big event
in January.

Intermission

I spent the next two months eating as much as I could (which was not much, I
was still suffering a bit from the peritonitis) and exercising on the
stationary bike, 20 minutes per day. Then the date was set, 19th January.

Part two

I arrived at 7am January 19th as requested at Oxford Churchill, and the
anaesthetists went into action. They stuck things into me, and eventually
asked me what I was there for. "Full brain transplant" I said and they
laughed, but I didn't because I was suddenly unconscious.

The operation took nine hours and five surgeons - it's the biggest they do in
Churchill.

I woke up in purgatory. They call it the Intensive Care Unit. My mouth was as
dry as a desert, but when I called for the nurse, all I got was a wet sponge
to suck. I had to do this several times. Meanwhile, the noise level was high -
phone ringing, people chatting, large things being dragged noisily across the
floor.

On my second day there, they got me to walk round the ward, and that was good
enough for them to transfer me to the upper gastrointestinal (UGI) ward, the
same place I was in November. I was able to greet many of the nurses by name.
They put me in a room for four, and I settled down. I had been told that I'd
be there for 10-30 days, depending on complications.

At that point, I had two things in my side, giving me timed and measured doses
of painkiller, I had a catheter, a big cannula in the big wrist vein on my
left, another big cannula in my jugular on the right, and a small one in my
right arm. And so I rested.

The doctor team came round, and I was told that the operation as 100%
successful, and now they were analysing the histology. That took a few days
more, and also came back 100%. And at that point, I was no longer a person
with cancer, I am now a cancer survivor.

The worst parts of the ICU was when a nurse dropped the catheter bottle and it
went all over the floor - not my problem, but when it dropped, it jerked the
tube, and the sudden pain made me scream.

I also got into a big row about my eye drops. I take wo different kinds in my
left eye (glaucoma, but it's under control). First, the nurse claimed that I
only had one set of drops, then she claimed that I didn't take eye drops at
all, because it wasn't on her computer. So I pointed out that both of them was
on my printed list of medications that I had brought in, in the bag of
medications. Eventually, I stopped arguing. And they found my list of
medications, and agreed that I was right. And then they lost one of the two
bottles, and couldn't find it. That was fixed when they did a new prescription
for it.

I was so glad to get out of ICU!

After a couple of days in UGI, they took out the painkillers in my sides.
After a couple more days, they took out the catheter, which wasn't painful,
but the first time I tried to urinate (into a bottle) what came out was red.

I have to admit, that made me very worried. I called a nurse, she called a
doctor, and he spent quite a long time with me reassuring me that although it
was normal, it was quite common, and was caused by some minor damage inside,
and would clear up in a couple of days. And he was right. But when I looked at
what first came out into that bottle, it was natural to worry.

The next several days were spent mostly sleeping, plus a little bit of
exercise, and a little bit of eating. As soon as I felt a bit better, I got
someone to bring in a small side table, she set my laptop up for me, and I was
able to log in to my network, and everything was running smoothly.

But ... my left forearm became very sore - it was phlebitis, an inflammation
of the veins, brought on by all the needles. The nurse told me it would clear
up in a week, and it did.

I started doing ward rounds. I'd get up, put on a dressing gown, walk round
the rooms in the ward, and if a door was open and the patient was awake, I'd
stick my head in and ask "Fancy a chat?". This was usually well received, so
I'd come in (masked) and we'd sit and chat for a while, about why we were
here, and our professions, about our children, hobbies and that sort of thing.
I did this almost every day.

On February 8th, the consultant decided I was ready to go home, hurrah!



Tuesday, 18 January 2022

Day 673 of self-isolation - The post arrived!

The post arrived!

The post arrived today - in large numbers. We got 30 letters, that being the cumulative buildup pf post over the last month or so.

For example, one letter from Oxford Hospitals was dated 10th December, and asked me to come in for an XR chest examination, which I have not done because I didn't know about it. And there were some other letters from Oxford Hospitals about appointments that I have kept, because I told them that if they want me, the MUST email or text about the appointment.

There were numerous letters from the bank about routine matters, a couple of magazines, and a wifi antenna.

We've been having this problem with our post for some months now, and I've been told it's because of staffing problems. But I cannot imagine what kind of staffing problems would lead to letters arriving more than a month after dispatch.

We're going to make a formal complaint about this.